Baca was born in Belen, New Mexico in 1947, the youngest of 15 children in a primarily Spanish-speaking household.[8] His father was a railroad laborer.[8] The family moved to Barstow, California when Joe was young, where he shined shoes at age 10, delivered newspapers, and later worked as a laborer for the Santa Fe Railroad, until he was drafted in 1966, serving in the United States Army until 1968. He did not serve in Vietnam.[9][10]

He served on the House Financial Services Committee, where he was a member of the Subcommittee on Capital Markets, Insurance, and Government Sponsored Enterprises, and the Subcommittee on Financial Institutions and Consumer Credit. Rep. Baca also served on the House Agriculture Committee, where he was the ranking member of the Subcommittee on Departmental Operations, Oversight, Nutrition and Forestry.

Rep. Baca was the Chair of the CHC Corporate America Task Force, which aims to increase Hispanic representation in corporate America.[citation needed] He created and co-chaired the Congressional Sex and Violence in the Media Caucus. Other caucus memberships included the Congressional Diabetes Caucus, the Military/ Veterans Caucus, the Native American Caucus and the U.S.-Mexico Caucus.

Only a few months after Baca was elected to the state senate, Congressman George Brown, Jr., the longest-serving member of either house of Congress in California's history, died after a long illness. Baca finished first in a seven-way primary, but fell far short of a majority due to the presence of two minor Democratic candidates. In the runoff, Baca defeated Republican Elia Pirozzi with 50.4%. He won the seat in his own right in 2000 with 59% of the vote. Brown had faced several unusually close races over the years and the state legislature had been looking to shore up the district even before his death. After the 2000 census, the district was renumbered as the 43rd and reconfigured as a majority-Hispanic district. Baca was handily reelected from this redrawn district in 2002, and didn't face another close contest again until 2012.

After the 2010 United States Census, the Citizens Redistricting Commission significantly redrew California's congressional map. The bulk of Baca's former territory became the 35th District, though his home in Rialto was placed in the 31st District. Baca opted to run in the 35th, and finished first in the all-party primary with 46.7 percent of the vote. His nearest opponent, State Senator Gloria Negrete McLeod, took 34 percent. In the general election, Negrete McLeod defeated Baca, taking 56 percent to Baca's 44 percent. A few weeks leading up to the election McLeod's campaign benefited from $3.2 million in independent expenditures from the Federal Super PAC of billionaire Michael Bloomberg, who was Mayor of New York City at that time. The Super PAC ran negative advertisements in newspapers, radio, and television accusing Baca of being soft on crime and causing perchlorate water contamination in drinking water. Bloomberg had become unhappy with Baca because he had not been supportive of Bloomberg's efforts for stronger federal laws for gun control and the enactment of federal registration.

According to the Los Angeles Times, Baca, chairman of the Congressional Hispanic Caucus, directed Caucus funds from its PAC[13] BOLDPAC (Building Our Leadership Diversity)[14] to the unsuccessful California campaigns of his sons, Joe Baca, Jr. and Jeremy Baca. At the time, Rep. Loretta Sanchez (D-CA) and five other members dropped out of the PAC in protest of these actions.[13] They alleged that the funds, meant to elect Hispanic candidates, should not have been used to help Baca's sons run against Hispanic candidates and that in a previous race funded by the PAC, Joe Jr. had run against Hispanic candidates.[14]

Citizens for Responsibility and Ethics in Washington (CREW) released a report stating that Rep. Baca had paid his daughter $27,000 from campaign funds and donated more than $20,000 to his sons' political campaigns from his own campaign funds.[15] They reported accusations that were made in 2006 by former members of Baca's Washington staff that they were sent to California in 2004 for a staff retreat and pressured to work on Joe Baca, Jr.'s campaign for the state Assembly on their paid time for the senior Baca.[8]

In January 2007, fellow Hispanic Caucus members including Loretta Sanchez, Nydia Velázquez (D-NY), Hilda Solis (D-CA) and Sanchez's sister Linda Sánchez (D-CA) wrote a letter to Baca asking for a new election with a secret ballot. They claimed that Baca was elected chair of the Caucus in a public ballot, despite Caucus rules for electing a chair that require a secret ballot election. On January 31, 2007, The Politico reported that Rep. Baca had called Loretta Sanchez a "whore". Citing Baca's alleged insult and the perceived impropriety in Baca's election to chairman of the CHC, as well as Baca's treatment of Latina members in the CHC, Loretta Sanchez resigned from the Caucus along with her sister, three other female California members and one female member from Arizona. Rep. Baca denied making the insult.[16] Reps. Loretta Sanchez and Hilda Solis alleged Rep. Baca made the remark in the summer of 2006. The two congresswomen state that they heard the remark from unnamed sources, although The Politico identified California State Assemblyman Fabian Núñez as one of those who heard the insult firsthand and told Loretta Sanchez.[17] She said that Baca confirmed the comments to her sister Linda Sánchez the day before Loretta Sanchez confronted him over the accusation.[13]

In March 2012, Baca and Rep. Frank Wolf (R-VA) introduced a bill that would force video game companies to put warning labels on their products. H.R. 4204, the Violence in Video Games Labeling Act, would compel game companies to label their products with "WARNING: Exposure to violent video games has been linked to aggressive behavior”.[citation needed]

In a February, 2014 interview in The Hill, Baca described Representative Gloria McLeod, who had defeated him in the 2012 elections after receiving $3.2 million in help from then New York Mayor Michael Bloomberg's Super PAC in the final weeks leading up to the election, as “some bimbo.” Minutes later he apologized, saying he was upset because he felt it was a disservice to the voters that she had announced the day before that she would not seek re-election to the congressional seat after holding it for only two years.[20]

Baca and his wife, Barbara, began their own business, Interstate World Travel, in San Bernardino in 1989. They have four children: Joe Jr., Jeremy, Natalie and Jennifer. Son Joe Baca, Jr. served one term as state assemblyman for California's 62nd district.

^"Joe Baca (D)". The Wall Street Journal. 2012. Retrieved 27 January 2013. Baca worked as a laborer for the Santa Fe Railroad before getting drafted into the U.S. Army in 1966. He served as a paratrooper during the Vietnam War, but did not see combat. He was discharged in 1968.